Thanks for what I consider a most agreeable contribution.I was not aware of your material on stackexchange, which seemsto be rather nice.

You are right that my example regarding mutable Lists in Mathematicawas incorrect. Actually on two grounds. The syntax was not right andI did not mean to say that Lists in Mathematica are not mutable, sincethey certainly are.

Just that Lists have the uncomfortable property that if you access one element,all the others are re-evaluated. Here is an example, which I think is free ofmis-used syntax...

( q=Table[f[i],{i,1,3}]; f[n_]:=(Print[n];g[n]))

q[[2]]

evaluates to display123g[2]

Changing q by, for example, q[[2]]=hellodoes not re-evaluate the elements.However, referring to in again as q[[2]] does this:13hello